Combined burglar-alarm and lock.



PATENTED MAY 9, 1905.

W. P. JOHNSON.

COMBINED BURGLAR ALARM AND LOOK.

APPLICATION FILED MAY 3. 1904.

TTT

Unirse France Fatented May 9, 1905.

Barner Drrlcn.

@@lll'lBllhllED BUWGLAHMALAHWH AND LUCK.

SPECIFICATION forming part of Letters Patent No. 789,546, dated May 9,1905,

Application filed May 3, 1904:- Serial No. 206,212.

Be it known that l, WiLLiAM PLEASANT JOHNSON, a citizen oil the UnitedStates, residing at Marion Junction, in the county of Dallas and Stateo'l Alabama, have invented a new andV useful Combined Burglar-Alarm andLock, ot which the following is a specilication.

My invention is an improvement in a combined burglar-alarm and leek.

The object ol my invention is to provide a lock with an audible-alarlnattachment in which the locking device will have a limited movementwithout releasing the door, window, or blind to which it is attached,said :movement being sufficient, however, to release a spring-actuatedalarm.

My invention consists in the novel features ol construction andcombination of parts hereinafter described, particularly pointed out inthe claim, and shown in the accompanying drawings, in which- Figure 1 isa perspective view showing my device applied and in locking position toa window-'frame and to the window-blinds. Fig. 2 is a view of my devicein locking position and applied to a door. Fig. 3 is a longitudinalsection showing my device in locking positien.. Fig. 4 is a similar viewshowing limit of movement of the locking device and position lirstassumed by the trigger ot the alarm when it has been released from saiddevice. Fig. 5 is a section on the line 5 5 of Fig.

My device comprises a metal plate A, havc ing inwardly-bent l'langes A',and this plate is adapted to be secured. by screws to a window-framecasing, windowwblind frame, or adjacent a door. A metal casing B, openat the top, has a bottom portion which slides on the plate A and is heldto same by the `llanges A. A block B at the forward end of the platecarries an upwardly-proj ccti ng plug A trigger (l is pivoted adjacentthe rear oll the casing and carries the hammer-head C', adapted to fallupon the plug B2. To the rear of the pivotal point the trigger is formedwith a shoulder C2. A spring B, having a length greater than thedistance between the pivotal point of the trigger and the block B, hasits forward end secured in the block and its .rear end secured to thetrigger below the pivotal point and in advance olithe shoulder. Astop-block D is arranged at the rear end of the casing, its uppersurface having a shallow recess Vformed in it. Above theblock Dispivoted a locking member D, having a notched. portieri D2 on its u nd ersu rliace, which notched. portion `is adapted to engage a pin lil,carried b y the d oor, window, or blind to be fastened. The lockingmember D has two shoulders D3 and Di, one on each side of the block Dand adapted to contact therewith and limit the swinging movement of thelocking member.

The operation of my device is as follows: The casing is slipped by handalong the baseplate A until the notch l)2 ol the locking member Dengages the pin Fi. rlhc trigger C is then thrown rearward until theshoulder C2 is locked under the shoulder D of the locking member, theshoulder DL bearing on the block D. lf an attempt is made to raise awindow or open a door or blind to which. the pin E is attached, thelocking member D will be lifted by the pin, the shoulder D bearing onthe shoulder C2 and forcing the trigger C into the position shown inFig. 4, when the shoulder D will pass the shoulder C2 and engage theblock D, stopping further movement of the locking member and stillretaining the notched portion l)2 in engagement with the pin E. As soonas the shoulder Ui is free from engagement with the shoulder D3 thespring B:i will draw the hammer-head C down on. the plug B2, and ill anexplosive cap has been placed on the plug it will be cX- ploded by theblow of the head C and an audiblesignal given, showing that an attempthas been made to open. the door, window, or blind.

lilaving thus lully described my invention, what l claim as new, anddesire to secure by Letters Patent, is

A device of the kind described comprising a casing, a block carriedthereby having an upwardly-projecting plug, a trigger pivoted in thecasing and adapted to engage the plug,

a spring of greater length than the distance shoulder on the trigger midthe pin simultabetweeii the bioek and the pivotal point of neousiy andto release the trlgger en hunted the trigger secured at 011e end to saidbleek movement 01 the sash.

and at the Opposite end to the trigger7 :i WILLIAM PLEASANT JOHNSON.shoulder O11 the trigger adjacent the pivotal Vitnesses:

point, 5L pin carried by the Window-sash, and M. F. SMITH,

it locking member adapted to engage the NV. S. REGISTER..

